New techniques in plant chloroplast division hold hope for agriculture

January 2003 -- Ground-breaking research at the University of Leicester into the
division of chloroplasts holds out hope of a safer way of genetically
modifying crops, with implications for agriculture particularly in the
developing world.

Using three plant types - Arabidopsis, tomato and rice - Dr Simon
Geir M'�ller has been working with colleagues in the University of
Leicester Department of Biology and at the Laboratory of Plant
Molecular Biology at the Rockefeller University in New York to examine
how chloroplasts divide in plants.

Chloroplasts make plants green
and are important organelles of plant cells and vital for life on
earth. Chloroplasts perform numerous tasks such as photosynthesis
(generation of oxygen) and the production of amino acids and fatty
acids. They have their own unique, and very small, genome, and are
derived from bacteria.

Comparing cell division in the E. coli
bacterium with the way chloroplasts divide, the research team has
isolated a new component of the division machinery in Arabidopsis,
AtMinE1, and they have shown that this protein represents an
evolutionary conserved link between bacterial division and chloroplast
division.

Dr M'�ller explained: "People have tried for a long
time to add genes to the chloroplast genome and adapt the levels of
proteins in them. You can engineer complex pathways in chloroplasts
that you can't achieve in a cell nucleus.

"The main advantage is
that chloroplasts are not spread by pollen, so there is no
environmental hazard in plants genetically modified in this way. In
other words there wouldn't be any cross-pollination or the development
of unwanted 'superweeds'. The gene basically dies with the plant.

"The
problem is that so far this has only been done in tobacco and once in
the tomato plant. Our research involves genetically controlled
enlarging of the chloroplasts, so that we can blast them more
efficiently with DNA attached to gold particles encoding valuable
proteins followed by re-manipulation of the division process."

The
work was recently published in The Plant Journal, in a report entitled
"The topological specificity factor AtMinE1 is essential for correct
plastid division site placement in Arabidopsis", by Dr Simon Geir
M'�ller and Jodi Maple of the University of Leicester Department of
Biology and Nam-Hai Chua of the Laboratory of Plant Molecular Biology,
the Rockefeller University, New York.

The research team is also
working with collaborators in the USA on putting vaccines into
chloroplasts of plants so that they can be eaten.

The research in
the laboratory of Dr Simon Geir M'�ller is funded by the Biotechnology
and Biological Sciences Research Council, The Royal Society, The John
Oldacre Foundation, The Ambrose and Ann Appelbe Trust and a HEROBC
Innovation Fellowship funded by HEFCE.